Had unprotected sex.

So I went out Friday night with my best friend and her boyfriend, her brother turned up half way though and then we all headed back to my friends house. We drank so much and then they went to bed leaving me with her brother and we slept together! I’m still in shock now that it happened and we never used anything. I looked the day after on my app and it said I was on my last day of being fertile. My period isn’t due until next weekend and I am so impatience and don’t think I can wait that long to take a test. I’m so frustrated. I wanna know if I am or not and tbh I don’t even know what I want to outcome to be, I’d love to be pregnant of course but I’m scared. I just wanna know!!!!